Intron 3 16 bp duplication polymorphism of TP53 contributes to cancer susceptibility: a meta-analysis.

A few genetic polymorphisms of TP53 are known to have a significant effect on cancer susceptibility. Intron 3 16 bp duplication polymorphism of TP53 has been reported to be associated with breast cancer, colorectal cancer, lung cancer and other cancers, but the reported results remain inconclusive. The present study, a meta-analysis including a total of 9801 cases and 10,391 controls from 26 studies, revealed that the 16 bp insertion (Ins) allele is significantly associated with an increased cancer risk in overall analysis [Ins/Ins + deletion (Del)/Ins versus Del/Del: odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.02-1.27, P = 0.02; Ins/Ins versus Del/Del: OR = 1.35, 95% CI = 1.11-1.63, P = 0.002; Del/Ins versus Del/Del: OR = 1.10, 95% CI = 0.98-1.23, P = 0.11.), particularly in breast cancer subgroup (Ins/Ins + Del/Ins versus Del/Del: OR = 1.16, 95% CI = 1.03-1.31, P = 0.02; Ins/Ins versus Del/Del: OR = 1.81, 95% CI = 1.30-2.52, P < 0.001; Del/Ins versus Del/Del: OR = 1.10, 95% CI = 0.97-1.25, P = 0.13). The relative risks to the colorectal and lung cancers increased but their association power was relatively weak, which may result from a limited number of studies of these two cancer types. These results suggest that intron 3 16 bp duplication polymorphism of TP53 is potentially an important and clinically relevant genetic marker contributing to cancer susceptibility.